The present invention relates to an improved upright piano, and more particularly relates to improvement in construction of an upright piano with a keyboard unit accommodatable in the main casing for easier transportation and storage.
An upright piano of the above-described type has already been proposed. In one well-known example, a keyboard unit is detachably or pivotally coupled to a pair of sides of the upright piano. More specifically, each side arm of the keyboard unit is secured to the corresponding side by means of holder metals and set screws. For accommodation of the keyboard unit, one of the side arms is disengaged from one holder metal by removal of the set screw and the keyboard unit is turned downwards about the rear end of the other holder metal in order to be encased in a lower space within the main casing.
With this conventional construction, set screws for the holder metals have to be removed for every accommodation of the keyboard unit. In addition to troublesome manual removal, repeated removal and setting of the set screws makes the threaded holes in the side seriously idle, thereby causing rattle, unstable positioning of the keyboard assembly. In order to avoid such inconveniences, it is thinkable to embed proper nuts in the sides for repeated trouble-free engagement with the set screws. This solution, however, causes increase in parts and troublesome assemblage of the upright piano.